magazine issue 4 2014 / Issue 20

Grasping the grounded nature of mental simulation

• written by Ryan Elder & Aradhna Krishna
• edited by Norbert Schwarz

Tucker and Ellis (2004) later moved beyond product orientation to examine the impact of product size on mental simulations of motor behavior. Participants viewed objects and indicated as quickly as possible whether an object was natural or man-made. The apparatus the participants received had two buttons: one held between the thumb and forefinger, and the other held in the palm of the same hand. To indicate an answer, participants thus either pinched their fingers together or squeezed their palm. The researchers found that participants were quicker to categorize objects when the size of the object matched the response grasp. For example, participants were quicker to indicate a grape was natural with a pinch of the thumb and forefinger than a squeeze with the palm. Similarly, participants were quicker to indicate a hammer was man-made with a squeeze of the palm than a pinch. Again, these findings suggest participants’ minds are readied through mental simulation at a more automatic level.

These results are suggestive of the occurrence of mental simulation. Fortunately, these findings within a behavioral context have been corroborated by more exact measurements: neuroscience.

Neuroscientific evidence of mental simulation 

Despite a longstanding debate regarding whether sensory images exist in the brain in a modal manner (see Kosslyn, Ganis, & Thompson, 2001 for a brief review), recent neuroscience evidence provides overwhelming support for the notion that the same brain areas are active during actual perception are active during imagery of a sensory experience. Using brain-imagining technology (e.g., functional magnetic resonance imaging, fMRI), researchers have explored the activation of different brain areas during perception and conscious forms of imagery. The mapping of neural activity between perception and conscious imagery is not a one-to-one relationship; however, the overlap is significant and provides support that conscious imagery can be a perceptual experience.

The neuroscience literature has additionally shown that these perceptual images and their neural correlates are activated automatically, through mental simulation, in response to simply viewing pictures or reading words. For example, viewing pictures of food items (e.g., a hamburger or spaghetti) activates brain areas associated with taste (Simmons, Martin, & Barsalou, 2005). Reading words with strong smell characteristics (e.g., coffee or vomit) activates brain areas associated with smell (González et al., 2006). Additionally, mirror neuron evidence suggests that simply observing another perform actions leads to neural activity similar to oneself performing the same action (see Rizzolatti and Craighero 2004 for a review). This fMRI evidence shows that pictures and words of objects and experiences can lead to automatic mental simulations.

In addition to the behavioral evidence regarding motor simulation (Tucker and Ellis 1998, 2004), researchers have also used brain-imaging technology to examine motor simulation. For example, viewing and naming pictures of tools that can be grasped with the hand (e.g., a wrench) activated premotor areas of the brain to a greater extent than viewing and naming pictures of non-graspable items (e.g., an elephant; Chao & Martin, 2000). Grèzes and Decety (2002) replicated the findings from Tucker and Ellis (2001) and showed considerable overlap in brain activity for deliberately imagining a motor action with a tool and simply viewing a picture of the tool.

The neuroscience research provides compelling evidence for the existence of mental simulations at a more automatic level. What do these simulations ultimately mean for us in our daily lives? We next explore the applications of mental simulations, with a particular focus on consumer contexts.